A refrigeration cycle device includes a compressor, a condenser, an expansion valve (a decompressor), and an evaporator, and is configured such that refrigerant circulates in a closed refrigerant circuit. R410A refrigerant as hydrofluorocarbon (HFC) has been broadly used as the refrigerant. However, the R410A refrigerant has a great global warming potential (GWP). In a known related technique, hydrofluoroolefin (HFO) 1123 refrigerant and a refrigerant mixture containing the HFO1123 refrigerant are used as refrigerant having a relatively-small GWP
Note that the technique of this area is disclosed in WO 2012/157764 A, for example.